Question

我正在使用directx11，我创建光源（平行光源）和场景（从obj文件加载），并且每件事看起来都正确但是当我在场景中旋转一些物体时，我的光也随着物体旋转，而且我不会旋转灯并保持固定。

我尝试通过这样做来解决问题，但我失败了：

XMMATRIX light_rotat = XMMatrixIdentity()

/*render the light*/



XMMATRIX light_rotat = XMMatrixRotationY(timeGetTime()/3500.0f);

/* render scene */

/ * hlsl代码* /

cbuffer LIGHT
{
    float4 light_color ; 
    float3 Direction ;
    float3 Position ;
    float3 attribute ; 
    float  Power ; 
    float range ; 
    float spotpower ;


};

cbuffer CAMERA
{
 float4x4 view ; 
 float4x4 world ; 
 float4x4 proj ; 
};

cbuffer local
{
float3 eye; 
float4x4 localworld ;

};
Texture2D texture_obj ;
SamplerState Texture_sampler ;
/* diffuse texture */
float4 Get_Texture (float2 uv  )

{
 return texture_obj.Sample (Texture_sampler , uv  );

}

/* light calc */
float4 Parrallel (float3 eye ,float3 Position ,float3 Normal , MTRL mtrl  )
{

float3 lightvec = normalize(-Direction) ;

float4 LitColor = float4(0.0f , 0.0f ,0.0f ,0.0f );

float diff_factor = dot(lightvec , Normal );
float4 diff = light_color * mtrl.Diffuse_Mtrl ;

if (diff_factor > 0.0f )
    {
        float4 amb = light_color * mtrl.Ambient_Mtrl ; 

        float3 view = normalize(eye - Position) ;


        float3 rf = normalize(reflect (Direction , Normal )) ;



        float4 Spec_Fac = pow ( max ( dot (rf ,  view ) , 0.0f ) , max (1.0f ,Power ));
        float4 Spec = light_color *  mtrl.Specular_Mtrl ;

         LitColor += ( diff *diff_factor) + (Spec_Fac*Spec) + (amb*diff_factor) ; 
    }
return LitColor ; 

} 

struct VS_INPUT
{
float4 Pos :POSITION ; 
float3 Normal : NORMAL0 ; 
float2 UV : TEXCOORD0 ; 
};


struct VS_OUT
{
float4 Pos :SV_Position ; 
float4 Posw : POSITION ; 
float4 Normal : TEXCOORD1 ; 
float2 UV : TEXCOORD0 ; 


};



VS_OUT VS (VS_INPUT input)
{
VS_OUT v ;





    v.Pos =  mul ( input.Pos  , localworld ); 
    v.Pos = mul (v.Pos , world ); 
    v.Pos = mul (v.Pos , view ); 
    v.Pos = mul (v.Pos , proj ); 


    v.Posw = mul ( input.Pos, localworld );  

    v.UV = input.UV ;

    v.Normal =  mul (float4(input.Normal , 0.0f) ,world ); 

return v ;
}


float4 PS (VS_OUT ps):SV_Target
{

    MTRL y ; 
    y.Diffuse_Mtrl = Get_Texture (ps.UV);
    y.Ambient_Mtrl = y.Diffuse_Mtrl /8 ; 
    y.Specular_Mtrl = float4 ( 0.5f , 0.5f , 0.5f , 0.0f );
    float4 licolor =  Parrallel ( eye , (float3)ps.Posw , (float3)ps.Normal ,y ) ;


    return licolor ;
}



technique11 tech2
{
pass P0
{
     SetVertexShader( CompileShader( vs_5_0, VS() ) );
     SetPixelShader( CompileShader( ps_5_0, PS() ) );
}

}

这是渲染循环

Device->Draw(Color);

t.localworld = ::XMMatrixTranspose ( XMMatrixRotationY ( timeGetTime() /3000.0f ) );
t.eye = XMFLOAT3( 0.0f, 10.0f, -30.0f );

local->UpdateSubresource (My_Buffer , 0 , NULL ,0, 0 , &t  );

ID3DX11EffectConstantBuffer *cm = effect->Get_Effect()->GetConstantBufferByName ( "local"); 
cm->SetConstantBuffer ( Local->Get_Buffer());


effect->Apply(Flags , Context);
mesh->draw();


Device->EndDraw();

任何帮助？

Answer 1

好的，'localworld'矩阵应该是这里的关键，你需要做的是创建一个旋转矩阵Y，并在你的渲染中将localworld变量写入HLSL之前，将localworld变量与此旋转矩阵相乘环。这应该只旋转你的顶点，你的光应该保持静止。

旋转物体，但保持照明固定DirectX？

1 个答案: